Interactions among Different Fractions in the Thermoplastic State of Goonyella Coking Coal
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- 作者：Takahiro Yoshida ; Toshimasa Takanohashi ; Masashi Iino ; Haruo Kumagai ; and Kenji Kato
- 刊名：Energy & Fuels
- 出版年：2004
- 出版时间：March 2004
- 年：2004
- 卷：18
- 期：2
- 页码：349 - 356
- 全文大小：171K
- 年卷期：v.18,no.2(March 2004)
- ISSN：1520-5029
文摘
Goonyella coking-coal was extracted with a 1:1 (v/v) carbon disulfide/N-methyl-2-pyrrolidinone(CS2/NMP) mixed solvent and then fractionated into four with pyridine and chloroform. High-temperature 1H NMR analysis conducted on each fraction and their mixtures in-situ showedthat the lightest, the chloroform-soluble fraction (CS), was rich in mobile hydrogen, Hm, thevariation of which with temperature corresponded to that of a thermoplastic parameter tan 
determined by in-situ viscoelastic measurement. In contrast, chloroform-insoluble and pyridine-soluble (CIPS) and pyridine-insoluble (PIMS) fractions showed scant change in Hm withtemperature, although the intermediate hydrogen, Hint, increased upon heating. These resultsallow the different fractions to be characterized qualitatively on the basis of differences in hydrogenmobility. In mixtures of the continuous fractions, positive interactions occurred that enhancedthe value of tan as well as the overall hydrogen mobility. A single maximum was observed inthe tan response of these mixtures, which indicated that the heavier fractions were solvatedthrough the action of the lighter ones. In a discontinuous mixture of the fractions, molecularinteraction was slight compared to continuous mixtures; only the light fraction started to softenat low temperature and, as a result, a bimodal response occurred in tan . The thermoplasticresponse of coking coal can be modeled on a self-dissolution basis involving the ~50% of solvent-soluble components that are present in whole coking coals and which possess a continuous fractiondistribution from light to heavy. The mobility of the system develops continuously upon heatingas a result of the progressive solvating action of the lighter components facilitating dissolutionand/or dispersion of the heavier components.
determined by in-situ viscoelastic measurement. In contrast, chloroform-insoluble and pyridine-soluble (CIPS) and pyridine-insoluble (PIMS) fractions showed scant change in Hm withtemperature, although the intermediate hydrogen, Hint, increased upon heating. These resultsallow the different fractions to be characterized qualitatively on the basis of differences in hydrogenmobility. In mixtures of the continuous fractions, positive interactions occurred that enhancedthe value of tan as well as the overall hydrogen mobility. A single maximum was observed inthe tan response of these mixtures, which indicated that the heavier fractions were solvatedthrough the action of the lighter ones. In a discontinuous mixture of the fractions, molecularinteraction was slight compared to continuous mixtures; only the light fraction started to softenat low temperature and, as a result, a bimodal response occurred in tan . The thermoplasticresponse of coking coal can be modeled on a self-dissolution basis involving the ~50% of solvent-soluble components that are present in whole coking coals and which possess a continuous fractiondistribution from light to heavy. The mobility of the system develops continuously upon heatingas a result of the progressive solvating action of the lighter components facilitating dissolutionand/or dispersion of the heavier components.